Uveitis and rheumatic conditions

Uveitis means inflammation of the uvea, the pigmented middle layer of the eye that includes the iris. Doctors describe it by where the inflammation sits. Anterior uveitis affects the front of the eye and is also called iritis; intermediate uveitis affects the area just behind it; posterior uveitis affects the back of the eye, near the retina; and panuveitis involves the whole of the uvea. Anterior uveitis is much the most common form and the one most often linked to rheumatic disease.

It usually comes on over hours to a day or two as a painful, red eye that is sensitive to light. Inflammation further back in the eye can be quieter, blurring vision or causing floaters with little or no pain, which is one reason some people at risk are followed with regular eye checks even when their eyes feel normal.

Anterior uveitis has a strong association with the spondyloarthritis family of inflammatory conditions, many of which share the genetic marker HLA-B27. These include axial spondyloarthritis, psoriatic arthritis, reactive arthritis and the arthritis that can accompany inflammatory bowel disease, known as enteropathic arthritis. In these conditions the uveitis is typically acute, affects one eye at a time and settles with treatment, although it can recur.

Other rheumatic conditions are linked with different patterns of eye inflammation. Behçet's disease can inflame the front or the back of the eye and needs careful monitoring, and sarcoidosis is another recognised cause. Adults who had juvenile idiopathic arthritis as children may carry a history of chronic anterior uveitis that was often silent, picked up only through regular eye screening, and this history stays relevant to their care as adults.

An important point for rheumatology is that uveitis can be the first sign of an undiagnosed condition. Someone may have an episode of acute anterior uveitis with only mild or intermittent back or joint symptoms in the background, and it is the eye inflammation that first brings them to medical attention. This is why an ophthalmologist who sees recurrent or HLA-B27-related uveitis will often suggest a rheumatology review.

The symptoms depend on where the inflammation is. Acute anterior uveitis, the form seen most in rheumatology, usually causes:

• A red, painful eye, often just one at a time
• Marked sensitivity to light (photophobia)
• Blurred vision, or a sense that vision has dimmed
• A small or irregular pupil, or aching that is worse when focusing

Inflammation further back in the eye may cause floaters or blurred vision with little or no pain, which makes it easy to overlook. Because posterior and intermediate uveitis can be quiet, and because the chronic uveitis linked to childhood arthritis may cause no symptoms at all, people with a known risk are sometimes followed with regular eye checks even when their eyes feel normal.

A painful, red, light-sensitive eye is never something to wait on. It needs same-day assessment, and the urgency is set out again below.

Uveitis itself is diagnosed by an eye specialist, who examines the eye with a slit lamp, a microscope that shows the inflammatory cells inside it, and checks the eye pressure and the back of the eye. That examination confirms the uveitis, locates it and guides treatment.

A rheumatologist's role begins once uveitis is confirmed, particularly when it is recurrent, affects both eyes, or comes with joint, back, skin or bowel symptoms. The aim is to find or rule out an underlying condition. This may involve a careful history and examination, blood tests including inflammatory markers and the genetic marker HLA-B27, and imaging of the spine or affected joints where spondyloarthritis is suspected. Where a joint is involved, point-of-care ultrasound during the consultation can show inflammation directly; you can read more on the ultrasound clinic page. Bringing the eye and the musculoskeletal picture together in one assessment is often what leads to a clear diagnosis.

Treatment is led by ophthalmology and depends on the type and severity. Acute anterior uveitis is usually treated with steroid eye drops to settle the inflammation, often alongside drops that widen the pupil to ease pain and stop the iris from sticking. Most single episodes respond well and clear over a few weeks, with the drops reduced gradually rather than stopped suddenly.

When uveitis keeps coming back, affects the back of the eye, or threatens vision, systemic treatment may be needed, and this is where eye and rheumatology teams decide together. Conventional disease-modifying medicines such as methotrexate can reduce how often flares occur, and biologic medicines, particularly the anti-TNF drug adalimumab, are used for uveitis that is severe or recurrent, especially when it is linked to conditions such as Behçet's disease or spondyloarthritis. A helpful feature of several of these medicines is that they work across both the eye inflammation and the joint disease, so one treatment can address both. They are prescribed and monitored by specialists, at the lowest effective dose, with attention to the balance of benefit and risk.

Uveitis sits at the meeting point of two specialties, and it is managed best when they work together. The eye team looks after the inflammation itself and protects your sight; the rheumatology team looks for and treats any underlying condition and helps guide shared decisions about longer-term medicines. Good communication between them means a change in your eyes can prompt a review of your joints, and a change in your joints can prompt attention to your eyes.

In London, for example, Imperial College Healthcare NHS Trust includes the Western Eye Hospital, so eye and rheumatology teams can work within a single Trust. If you already attend an eye clinic for uveitis and have unexplained joint, back or other symptoms, mentioning this to either team helps make sure the whole picture is assessed.

Uveitis can threaten sight, so certain eye symptoms should never be left to a routine appointment.

Seek same-day assessment at an eye casualty or urgent eye clinic if you develop:

• A newly painful, red eye, especially with sensitivity to light
• Blurred, dimmed or reduced vision
• A known history of uveitis and symptoms that feel like a flare returning

Call 999 or go to A&E for sudden, complete loss of vision in an eye, which is a medical emergency.

If you have a known rheumatic condition, do not assume a red or painful eye is minor; have it checked the same day, because early treatment protects vision. Stable, long-standing joint symptoms can be reviewed routinely.

An episode of uveitis is worth taking seriously in its own right, and it can also be a valuable clue. For some people it is the first sign of a rheumatic condition that would otherwise take longer to recognise, and for those already diagnosed it can signal that the disease is active. A specialist rheumatology assessment, working alongside your eye team, can look for an underlying cause, interpret it in the light of your other symptoms, and set out a plan that protects both your joints and your sight. Recognising the link between the eye and the rest of the body is often what turns a frightening episode into a clear, manageable diagnosis.

Is uveitis always linked to a rheumatic condition?

No. Many people have a single episode of uveitis with no underlying disease, and some cases follow an infection. But anterior uveitis, the type at the front of the eye, is strongly linked to the spondyloarthritis family, including axial spondyloarthritis and psoriatic arthritis, and it can be the first sign of one of these conditions. This is why recurrent or HLA-B27-related uveitis often leads to a rheumatology review.

When is a red, painful eye an emergency?

A newly painful, red eye with sensitivity to light or blurred vision needs same-day assessment at an eye casualty or urgent eye clinic, because untreated uveitis can threaten sight. Sudden, complete loss of vision in an eye should be treated as an emergency. If you already know you get uveitis, do not wait on symptoms that feel like a flare returning.

How is uveitis connected to ankylosing spondylitis and related conditions?

Many of the spondyloarthritis conditions, including axial spondyloarthritis (which includes ankylosing spondylitis), reactive arthritis and the arthritis linked to inflammatory bowel disease, share the genetic marker HLA-B27. People who carry it have a higher chance of acute anterior uveitis, which typically affects one eye at a time, comes on quickly and settles with treatment, though it can recur.

How is uveitis treated?

Treatment is led by an eye specialist. Acute anterior uveitis is usually treated with steroid eye drops, often with drops that widen the pupil to ease pain, and most single episodes clear within a few weeks. When uveitis keeps returning or threatens vision, eye and rheumatology teams may add tablet or injectable medicines such as methotrexate or adalimumab, several of which treat both the eye inflammation and the associated joint disease.

Why have I been referred to a rheumatologist after uveitis?

Because uveitis can be the first sign of an underlying rheumatic condition, particularly when it is recurrent, affects both eyes, or comes with back, joint, skin or bowel symptoms. A rheumatology assessment looks for or rules out a condition such as axial spondyloarthritis or Behçet's disease, using examination, blood tests and, where a joint is involved, ultrasound in the clinic. Finding a cause means it can be treated, which can also reduce further eye flares.